(Solved): A buffer solution contains \( 0.100 \mathrm{~mol} \) of acetic acid \( \left(\mathrm{K}_{\mathrm{s} ...

A buffer solution contains \( 0.100 \mathrm{~mol} \) of acetic acid \( \left(\mathrm{K}_{\mathrm{s}}=1.8 \times 10^{-5}\right) \) and \( 0.130 \mathrm{~mol} \) of sodium acetate in \( 2.50 \mathrm{~L} \) of solution. CH3 COONa a) Determine the initial \( \mathrm{pH} \) of the solution. (4 marks) \[ \begin{array}{l} P H=P K a+\log \left(\frac{[A-]}{[H A]}\right) \\ P H=-\log \left(1.8 \times 10^{-5}\right)+\log \left(\frac{0.130}{0.100}\right) \\ P H=4.74+0.114 \end{array} \] b) Determine the \( \mathrm{pH} \) of the solution after the addition of \( 0.0200 \mathrm{~mol} \) of \( \mathrm{KOH} \). c) Determine its \( \mathrm{pH} \) after the addition of \( 0.200 \mathrm{~mol} \) of \( \mathrm{KOH} \). ( 5 marks)